A pedestal liner

ABSTRACT

A pedestal liner which includes an elongate body and a bearing formation mountable about the elongate body for in use, defining a bearing surface of the elongate body, wherein the bearing formation has a coefficient of friction value less than that of the elongate body.

TECHNICAL FIELD OF THE INVENTION

This invention relates to a pedestal liner and to a bearing formation for a pedestal liner.

BACKGROUND TO THE INVENTION

Pedestal liners manufactured from low friction composite materials are well known in the art.

These types of pedestal liners are typically contoured and shaped to be mounted about a pedestal leg of the bogie, or about the axle box, of a typical railway vehicle such as a train wagon, train car, train truck, or the like. The bearing surface of the pedestal liner is typically interposedly arranged between the pedestal leg and the axle box to facilitate slidable displacement between these moving parts so as to minimise friction and to promote free movement of the axle, vertically and laterally, with a resultant reduction in wheel wear, flange wear, rail wear and wheel-rail squeal.

Composite materials having a relatively low coefficient of friction (CoF) value are associated with having relatively low impact and/or mechanical strength, thus while composites having relatively low CoF values may be suitable to enhance slidable displacement between moving parts, these types of composites typically lack the required degree of impact and/or mechanical strength to, when in use, withstand the forces impacting on the pedestal liner.

The need therefore exists for a pedestal liner having improved bearing surface characteristics, while at the same time having a certain degree of impact and/or mechanical strength.

The inventor having considered the above proposes the invention as set out hereunder.

For the purpose of this specification the phrase “axle box” shall mean to include the structure mounted on the wheel set, acting as link between the rotating wheel set and the bogie frame. Typically, the axle box is seated between a pair of spaced apart pedestal legs of the bogie frame.

For the purpose of this specification the phrase “pedestal legs” shall mean to include the pair of downward extending legs of the bogie side frame, the pair of downward extending pedestal legs being spaced apart so as to receive the axle box.

SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided a pedestal liner which includes

an elongate body; and

a bearing formation mountable about the elongate body for in use, defining a bearing surface of the elongate body;

wherein the bearing formation has a coefficient of friction value less than that of the elongate body.

The pedestal liner may be releasably secured to the pedestal leg, or, axle box, in any suitable manner.

The pedestal liner may be displacably arranged in between the pedestal leg and axle box to the pedestal leg so as to float therein between, wherein the degree of displacement is regulated by one or more stopping formations.

The elongate body may include a mounting formation for mounting the pedestal liner about a pedestal leg, or, axle box.

The mounting formation may take the form of a flange extending away from a longitudinal side of the elongate body to define a substantially L—shaped pedestal liner in transverse cross section.

The mounting formation may take the form of a pair of flanges extending away from the elongate body and arranged longitudinally with the elongate body so as to define a substantially U—shaped pedestal liner in transverse cross section.

The elongate body may include one or more apertures for receiving a fastener such as a bolt and nut for mounting the pedestal liner onto a pedestal leg, or, axle bearing box.

The mounting formation may include one or more apertures for receiving a fastener such as a bolt and nut for mounting the pedestal liner onto a pedestal leg, or, axle bearing box.

The elongate body and/or the mounting formation may further include a receiving formation for complementarily receiving the bearing formation.

The receiving formation may take the form of a recess defined about an outer facing surface of the elongate body.

The receiving formation may take the form of a plurality of recesses defined in a spaced apart manner about the outer facing surface of the elongate body and/or the mounting formation.

The receiving formation may take the form of an aperture defined about the elongate body and/or the mounting formation.

The receiving formation may take the form of a plurality of apertures defined in a spaced apart manner about the elongate body and/or the mounting formation.

The bearing formation may be disc shaped.

One surface of the bearing formation may take the form of a bulbous and/or convex shaped formation.

The bearing formation may have a thickness dimension such that when located in the receiving formation, the bearing formation protrudes about the outer facing surface of the elongate body and/or the mounting formation, the outer protruding surface defining the bearing surface.

The bearing formation may have a thickness dimension such that when located in the receiving formation, the bearing formation is flush with the outer facing surface of the elongate body and/or the mounting formation, the outer surface defining the bearing surface.

The bearing formation may be dimensioned relative to the wall thickness of the pedestal liner so as when located in the aperture, the bearing formation is flush with an inner facing surfaces of the elongate body and/or mounting formation.

The bearing formation may be kept in place in the receiving formation by incorporating a suitable adhesive.

The bearing formation may be shaped and sized to, in use, fit into the receiving formation in a friction fit manner.

The receiving formation and bearing formation may be respectively dimensioned so as to define a retaining arrangement for, in use, retaining the bearing formation in the receiving formation in a fixed manner.

The receiving formation and bearing formation may be respectively dimensioned so as to define a retaining arrangement for, in use, releasably retaining the bearing formation in the receiving formation.

The retaining arrangement may include a female type formation defined circumferentially about, and preferably centrally, an outer surface of the bearing formation.

The female type formation may take the form of a groove defined circumferentially about an outer surface of the bearing formation.

The retaining arrangement may further include a male type formation defined circumferentially about, and preferably centrally, an inner facing surface of the receiving formation for mating with the female type formation to retain the bearing formation therein.

The male type formation may take the form of a ridge extending circumferentially about an inner facing surface of the receiving formation.

The retaining arrangement may be configured to retain the bearing formation in the receiving formation in an interlocking manner.

The bearing formation may have a maximum coefficient of friction value of about 0.1 when employing the internationally recognised formula as set out in document ASTM D3702—94(2019) entitled “Standard Test Method for Wear Rate and Coefficient of Friction of Materials in Self-Lubricated Rubbing Contact Using a Thrust Washer Testing Machine”.

The elongate body and/or mounting formation may be manufactured from a synthetic or metallic material.

The synthetic material may include a polymer material, or a mixture wherein the mixture includes a polymer material.

The elongate body and/or mounting formation may be manufactured from a material having resiliently deformable properties.

According to a second aspect of the invention there is provided a bearing formation for in use, defining a bearing surface of a pedestal liner, which bearing formation is manufactured from a material having a coefficient of friction value less than that of the pedestal liner.

The bearing formation may be disc shaped and configured to be complementarily received by a receiving formation defined about the pedestal liner.

The receiving formation may take the form of a recess defined about an outer facing surface of the pedestal liner.

The receiving formation may take the form of a plurality of recesses defined in a spaced apart manner about the outer facing surface of the pedestal liner.

The receiving formation may take the form of an aperture defined in the pedestal liner.

The receiving formation may take the form of a plurality of apertures defined in a spaced apart manner in the pedestal liner.

The bearing formation may be in the form of an insertable bearing formation.

The bearing formation may be shaped and sized to be complementarily received by the receiving formation.

The bearing formation may be disc shaped.

One surface of the bearing formation may take the form of a bulbous and/or convex shaped formation.

The bearing formation may have a thickness dimension so as to when located in the receiving formation, the bearing formation protrudes about the outer facing surface of the pedestal liner, the outer protruding surface defining the bearing surface.

The bearing formation may also have a thickness dimension such that when located in the receiving formation, the bearing formation is flush with the outer facing surface of the pedestal liner, the outer surface defining the bearing surface.

The bearing formation may be dimensioned relative to the wall thickness of the pedestal liner so that when located in the aperture, the bearing formation is flush with an inner facing surface of the pedestal liner.

The bearing formation may be kept in place in the receiving formation by incorporating a suitable adhesive.

The bearing formation may be shaped and sized to, in use, fit into the receiving formation in a friction fit manner.

The receiving formation and bearing formation may be respectively dimensioned so as to define a retaining arrangement for, in use, retaining the bearing formation in the receiving formation in a fixed manner.

The receiving formation and bearing formation may be respectively dimensioned so as to define a retaining arrangement for, in use, releasably retaining the bearing formation in the receiving formation.

The retaining arrangement may include a female type formation defined circumferentially about, and preferably centrally, an outer surface of the bearing formation.

The female type formation may take the form of a groove defined circumferentially about an outer surface of the bearing formation.

The retaining arrangement may further include a male type formation defined circumferentially about, and preferably centrally, an inner facing surface of the receiving formation for mating with the female type formation to retain the bearing formation therein.

The male type formation may take the form of a ridge extending circumferentially about an inner facing surface of the receiving formation.

The retaining arrangement may be configured to retain the bearing formation in the receiving formation in an interlocking manner.

The bearing formation may have a maximum coefficient of friction value of about 0.1 when employing the internationally recognised formula as set out in document ASTM D3702—94(2019) entitled “Standard Test Method for Wear Rate and Coefficient of Friction of Materials in Self-Lubricated Rubbing Contact Using a Thrust Washer Testing Machine”.

The pedestal liner may include a mounting formation for mounting the pedestal liner about a pedestal leg, or, axle box.

The mounting formation may take the form of a flange extending away from a longitudinal side of the elongate body to define a substantially L—shaped pedestal liner in transverse cross section.

The mounting formation may take the form of a pair of flanges extending away from the elongate body and arranged longitudinally with the elongate body so as to define a substantially U—shaped pedestal liner in transverse cross section.

The pedestal liner may be manufactured from a synthetic or metallic material.

The synthetic material may include a polymer material, or a mixture wherein the mixture includes a polymer material.

The pedestal liner may be manufactured from a material having resiliently deformable properties.

The pedestal liner may be releasably secured to the pedestal leg, or, axle box, in any suitable manner.

The pedestal liner may be displacably arranged in between the pedestal leg and axle box to the pedestal leg so as to float therein between, wherein the degree of displacement is regulated by one or more stopping formations.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described by way of the following, non-limiting example with reference to the accompanying drawings.

In the drawings: —

FIG. 1 is a top perspective of the bearing formation;

FIG. 2 is a cross sectional side view of the bearing formation shown in FIG. 1 ;

FIG. 3 is a top view of the bearing formation shown in FIGS. 1 and 2 ;

FIG. 4 is a bottom perspective of the pedestal liner showing the receiving formations in the form of apertures;

FIG. 5 is a bottom perspective illustrating the pedestal liner shown in FIG. 4 with bearing formations;

FIG. 6 is a top perspective of FIG. 5 ;

FIG. 7 is a transverse cross section of the pedestal liner shown in FIGS. 5 and 6 ;

FIG. 8 is a bottom perspective of the pedestal liner showing the receiving formations in the form of recesses;

FIG. 9 is a top perspective of the pedestal liner shown in FIG. 8 ;

FIG. 10 is a bottom perspective of a pedestal liner illustrating the arrangement of bearing formations on a flange of the pedestal liner, in accordance with the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

In the drawings, reference numeral 10 generally depicts a pedestal liner in accordance with the invention.

Accordingly, there is provided a pedestal liner 10 which includes an elongate body 12, and a bearing formation 14 mountable about the elongate body 12 for in use, defining a bearing surface 16 of the elongate body 12, wherein the bearing formation 14 has a coefficient of friction value less than that of the elongate body 12.

The pedestal liner 10 can be releasably secured to a pedestal leg, or, axle box, in any suitable manner and, alternatively, be displacably arranged in between the pedestal leg and axle box so as to float therein between, wherein the degree of displacement is regulated by one or more stopping formations (not shown).

In the figures shown the elongate body 12 includes a mounting formation in the form of a pair of flanges 18.1 and 18.2 for mounting the pedestal liner about a pedestal leg, or, axle box, the pair of flanges 18.1 and 18.2 typically extending away from the longitudinal sides of the elongate body 12 to define a substantially U—shaped pedestal liner in cross sectional view.

It is to be appreciated that the pedestal liner 10 described herein can also function in the absence of any flanges 18.1 and 18.2, and as such the elongate body 12 will be in the form of a flat plate which can be mounted onto any desired surface.

The pedestal liner 10 can also function having one flange 18.1 only where the pedestal liner 10 will define a substantially L shaped pedestal liner in cross sectional view.

The elongate body 12 and/or the flanges 18.1 and 18.2 will typically include one or more apertures 19 for receiving a fastener such as a bolt and nut for mounting the pedestal liner onto a pedestal leg, or, axle bearing box.

In order to facilitate the arrangement of the bearing formation 14 about the elongate body 12, the elongate body 12 further includes a receiving formation which can take the form of an aperture 20 as shown in FIG. 4 for complementarily receiving the bearing formation 14 therein.

Alternately, the receiving formation can take the form of a recess 22, as shown in FIG. 8 for complementarily receiving the bearing formation 14 therein. FIG. 9 being a top view of FIG. 8 illustrates the absence of any recesses 22 on the inner facing surfaces of the pedestal liner 10.

FIGS. 1 to 3 depicts the disc shaped bearing formation 14.

More clearly shown in FIGS. 5 and 10 , in use, the bearing formation 14 can have a thickness dimension such that when located in the receiving formation, the bearing formation 14 protrudes about the outer facing surface 24 of the elongate body 12, the outer protruding surface defining the bearing surface 16.

It is however appreciated that the thickness dimension of the bearing formation can also be such as to yield a bearing surface flush with an outer surface of the pedestal liner.

FIGS. 5, 6 and 7 depict bearing formation 14 typically dimensioned such that when located in the receiving formation which takes the form of an aperture 20, the bearing formation 14 is flush with an inner facing surface 25 of the elongate body 12 and/or the flanges 18.1 and 18.2.

The receiving formation and bearing formation 14 are respectively dimensioned so as to define a retaining arrangement for, in use, retaining the bearing formation 14 in the receiving formation.

The retaining arrangement includes a female type formation defined circumferentially about, and preferably centrally, an outer surface of the bearing formation 14.

More clearly shown in FIGS. 1 and 2 , the female type formation can take the form of a groove 26 defined circumferentially about an outer surface of the bearing formation 14.

The retaining arrangement further includes a male type formation defined circumferentially about, and preferably centrally, an inner facing surface of the receiving formation for mating with the female type formation to retain the bearing formation 14 therein.

FIGS. 4, 7 and 8 more clearly depict the male type formation in the form of a ridge 28 extending circumferentially about an inner facing surface of the receiving formation when in the form of aperture 20, more clearly shown in FIG. 4 , and recess 22, shown in FIG. 8 , the retaining arrangement retaining the bearing formation 14 in the receiving formation 20 and 22 in an interlocking manner.

It is further to be appreciated that the male and female type formations can be interchangeably defined about the receiving formation and the bearing formation, respectively, and that the embodiment shown is for illustrational purposes only.

It is also to be appreciated that bearing formation 14 can also be kept in place in the receiving formation by incorporating a suitable adhesive. Alternatively, bearing formation 14 can also be shaped and sized to, in use, fit into the receiving formation in a friction fit manner.

As shown in FIGS. 4, 5, 6, 8 and 10 , preferably a plurality of receiving formations will be defined in a spaced apart manner about the outer facing surface of the elongate body 12 and/or the flanges 18.1 and 18.2, of the pedestal liner 10. More specifically, FIG. 10 shows a typical spaced apart arrangement of bearing formations 14 about the outer facing surfaces of flanges 18.1 and 18.2

The bearing formation will preferably have a maximum coefficient of friction value of about 0.1 when employing the internationally recognised formula as set out in document ASTM D3702—94(2019) entitled “Standard Test Method for Wear Rate and Coefficient of Friction of Materials in Self-Lubricated Rubbing Contact Using a Thrust Washer Testing Machine”.

Abovementioned international standard was developed in accordance with internationally recognised principles on standardisation established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organisation Technical Barriers to Trade (TBT) Committee.

The elongate body 12 and/or flanges 18.1 and 18.2 can be manufactured from a synthetic or metallic material.

The synthetic material in turn can include a polymer material, or a mixture wherein the mixture includes a polymer material.

The elongate body and/or mounting formation can also be manufactured from a material having resiliently deformable properties.

The Applicant considers the invention advantageous in that a pedestal liner 10 is disclosed with improved bearing characteristics wherein the one or more bearing formations 14 defining the bearing surfaces 16 are manufactured from a material having a coefficient of friction (CoF) value lower than that of the remaining structure. This combination of use of materials yields a pedestal liner 10 which has high mechanical strength and can endure high impacts, while at the same time having improved bearing characteristics as the elongate body 12 and/or flanges 18.1 and 18.2 are manufactured from a more resilient material having the required mechanical strength to withstand the forces typically experienced by a pedestal liner when in use.

It shall be understood that the examples are provided for illustrating the invention further and to assist a person skilled in the art with understanding the invention and are not meant to be construed as unduly limiting the reasonable scope of the invention. 

1. A pedestal liner which includes an elongate body; a mounting formation for in use, mounting the pedestal liner; the elongate body including a receiving formation for complementary receiving a bearing formation therein; and wherein the bearing formation has a coefficient of friction value less than that of the elongate body.
 2. (canceled)
 3. (canceled)
 4. (canceled)
 5. (canceled)
 6. A pedestal liner as claimed in claim 1 wherein the mounting formation includes a receiving formation for complementarily receiving the bearing formation therein.
 7. A pedestal liner as claimed in claim 6 wherein the receiving formation takes the form of a recess.
 8. (canceled)
 9. A pedestal liner as claimed in claim 6 wherein the receiving formation takes the form of a plurality of recesses defined in a spaced apart manner about the outer facing surface of the mounting formation.
 10. A pedestal liner as claimed in claim 6 wherein the receiving formation takes the form of an aperture defined in the mounting formation.
 11. (canceled)
 12. A pedestal liner as claimed in claim 6 wherein the receiving formation takes the form of a plurality of apertures defined in a spaced apart manner about the mounting formation.
 13. A pedestal liner as claimed in claim 1 wherein the bearing formation takes the form of a disc.
 14. (canceled)
 15. A pedestal liner as claimed in claim 1 wherein the bearing formation has a thickness dimension relative to that of the elongate and/or mounting formation such that when located in the receiving formation, the bearing formation protrudes about an outer facing surface of the elongate body and/or mounting formation.
 16. A pedestal liner as claimed in claim 1 wherein the bearing formation has a thickness dimension relative to that of the elongate and/or mounting formation such that when located in the receiving formation, the bearing formation is flush with an outer facing surface of the elongate body and/or mounting formation.
 17. (canceled)
 18. (canceled)
 19. (canceled)
 20. (canceled)
 21. A pedestal liner as claimed in claim 1 wherein the bearing formation fit into the receiving formation in a friction fit manner.
 22. A pedestal liner as claimed in claim 1 wherein the receiving formation and bearing formation are respectively dimensioned so as to define a retaining arrangement for, in use, retaining the bearing formation in the receiving formation.
 23. A pedestal liner as claimed in claim 1 wherein the receiving formation and bearing formation are respectively dimensioned so as to define a retaining arrangement for, in use, releasably retaining the bearing formation in the receiving formation.
 24. A pedestal liner as claimed in claim 22 wherein the retaining arrangement comprises a female type formation defined circumferentially about an outer surface of the bearing formation, and, a male type formation defined circumferentially about an inner facing surface of the receiving formation for in use, mating with the female type formation for retaining the bearing formation therein.
 25. (canceled)
 26. (canceled)
 27. (canceled)
 28. A pedestal liner as claimed in claim 1 wherein the bearing formation has a maximum coefficient of friction value of about 0.1. 29-56. (canceled)
 57. A pedestal liner as claimed in claim 1 wherein the receiving formation takes the form of a recess defined about an outer surface of the elongate body.
 58. A pedestal liner as claimed in claim 1 wherein the receiving formation takes the form of a plurality of recesses defined in a spaced apart manner about an outer facing surface of the elongate body.
 59. A pedestal liner as claimed in claim 1 wherein the receiving formation takes the form of an aperture.
 60. A pedestal liner as claimed in claim 1 wherein the receiving formation takes the form of a plurality of apertures defined in a spaced apart manner about the elongate body.
 61. A pedestal liner as claimed in claim 1 wherein the mounting formation takes the form of a flange extending away from a longitudinal side of the elongate body to define a substantially L—shaped pedestal liner in cross sectional view.
 62. A pedestal liner as claimed in claim 1 wherein the mounting formation takes the form of a pair of flanges extending away from the elongate body and arranged longitudinally the elongate body so as to define a substantially U—shaped pedestal liner in transverse cross section.
 63. A pedestal liner as claimed in claim 23 wherein the retaining arrangement comprises a female type formation defined circumferentially about an outer surface of the bearing formation, and, a male type formation defined circumferentially about an inner facing surface of the receiving formation for in use, mating with the female type formation for retaining the bearing formation therein.
 64. A bearing formation for in use, defining a bearing surface of a pedestal liner, which bearing formation is manufactured from a material having a coefficient of friction value less than that of the pedestal liner and in region of maximum 0.1, the pedestal liner further including a receiving formation dimensioned for complementarily and receiving the bearing formation in a fixed manner therein. 